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Date: Wed, 28 Apr 2004 16:52:41 -0400 From: "Damien A" Subject: testdyngl fix The test program you included in the latest version of SDL crashes on startup in Window (XP). The reason for this is that OpenGL functions on Windows use the __stdcall calling convention, not the C convention. Placing APIENTRY infront of the * operator solves this problem.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 30 Apr 2004 18:33:30 +0000
parents 355632dca928
children
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<HTML
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>SDL_GetRGBA</TITLE
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><H1
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>SDL_GetRGBA</H1
><DIV
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><A
NAME="AEN1747"
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><H2
>Name</H2
>SDL_GetRGBA&nbsp;--&nbsp;Get RGBA values from a pixel in the specified pixel format.</DIV
><DIV
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>Synopsis</H2
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void <B
CLASS="FSFUNC"
>SDL_GetRGBA</B
></CODE
>(Uint32 pixel, SDL_PixelFormat *fmt, Uint8 *r, Uint8 *g, Uint8 *b, Uint8 *a);</CODE
></P
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></DIV
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><A
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></A
><H2
>Description</H2
><P
>Get RGBA component values from a pixel stored in the specified pixel format.</P
><P
>This function uses the entire 8-bit [0..255] range when converting color
components from pixel formats with less than 8-bits per RGB component
(e.g., a completely white pixel in 16-bit RGB565 format would return
[0xff, 0xff, 0xff] not [0xf8, 0xfc, 0xf8]).</P
><P
>If the surface has no alpha component, the alpha will be returned as 0xff
(100% opaque).</P
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><H2
>See Also</H2
><P
><A
HREF="sdlgetrgb.html"
>SDL_GetRGB</A
>,
<A
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>SDL_MapRGB</A
>,
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>SDL_MapRGBA</A
>,
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>SDL_PixelFormat</A
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